Uniform muzzle velocity pneumatic gun



April 21, 195 3 3 Sheets-Sheet 1 Filed Aug. 4, 1949 IN VDV TOR. Mu/AM 5. h/azs ll/l/K/ 3 Nb mi .m on b m 3 mm M w H n w 1% E E 6 S 8/ 8: a u //////Y/#/// 52/ 7/ 74 5 746 97/ m 2. M0 mm m mm q QQ NG Cb m mm .QQ mm 3 mm mz m bw MM 2 N Go 3 2 33 3 b m m April 53 w. s. WELLS 2,635,599

UNIFORM MUZZLE VELOCITY PNEUMATIC GUN Filed Aug. 4, 1949 '3 Sheets-Sheet 2 E1515 a 94 93 so 9 ---ll:|

99 as 65 87 H 106 as I05 29 68 I03 54. 69 I0] I02 72 73 4 '7| 6' IN V EN TOR.

W/u/AM 5. Wzus BY April 21, 1953 w. s. WELLS UNIFORM muzzmvmocnv PNEUMATIC GUN 3 Sheets-Sheet 3 Filed Aug. 4. 1949 Patented Apr. 21, 1953 UNIFORM MUZZLE VELOCITY PNEUMATIC GUN William S. Wells, Palo Alto, Calif., assignor to Daisy Manufacturing Company,

Plymouth,

Mich., a corporation of Michigan 7 Application August 4, 1949, Serial No. 108,566

This invention relates to pneumatic guns and more particularly to a repeating type pneumatic gun which will shoot a plurality of shots from a single compressed air charge, at a substantially, constant velocity, and is a continuation in part of applicants copending application for improvements in Mechanism 'for Maintaining Substantially Uniform Muzzle Velocity for Pneumatic Guns, Serial No. 762,391, filed July 21, 1947, and now abandoned.

The pneumatic gun of this invention is provided with .a storage chamber in which fluid under pressure is held for use in propelling shot, either of the ball or pellet type, through the gun barrel, at high velocities. The air in the chamber may be periodically replenished by suitable compressor means, forming either a part of or a separate unit from the gun itself. Valve means are provided for controlling the flow of air from the storage chamber to the gun barrel behind a projectile therein, and the valve is 12 Claims. (Cl. 124-13) operated in a novel manner through a trigger mechanism and hammer mechanism. The gun of this invention will fire a plurality of shots, after the storage chamber has been charged, at substantially the same muzzle velocity. The number of shots fired from a single air charge may be varied, and the gun of this invention can be arranged to shoot from.v one to one hundred shots, all at substantially the same velocity, without recharging the air chamber.

The number of shots which can be fired from a single air charge depends upon the number of shots the gun is designed to fire.

. In the past fifty years many people have attempted to produce a repeater type of air gun. It should at this time be pointed out that the word repeater, as used herein, means a gun which will shoot a plurality of shots, from a single air charge, all at a substantially uniform muzzle velocity. No one has heretofore succeeded in developing a repeating, self-contained pneumatic gun. Many people have, of course, developed pneumatic guns which will fire more than one shot from a single air charge, but such guns are not repeaters because the muzzle velocity of the plurality of shots is not sub-,- stantially uniform. The gun of this invention is designed primarily to shoot projectiles at relatively high velocities.

Such guns are quite generally used as target guns and must, therefore, be extremely accurate. If a plurality of projectiles are shot from a gun, and the muzzle velocities thereof vary materially, the accuracy of the gun is destroyed and the gun is not satisfactory as a target gun.

While guns have been developed in the past, which claim to be of the repeater type, none of these guns is va repeater in the sense referred to above." In one type of previously developed repeater gun, a valve is provided between the air storage chamber and a passageway leading to the gun barrel. This valve is resiliently held in its closed position by means of a spring and the valve is adapted to be opened, against the spring, by means of a spring actuated hammer. In this construction the valve spring is stronger than the hammer spring, so that the valve spring will close the valve after it has been opened by the impact of the hammer against the valve stem. Thus, the valve will be opened substantially the same amount each time it is hit by the hammer and as there is a fixed volume and pressure of air in the storage chamber, the pressure of air in the storage chamber will become less after each opening of the valves. As the valve opens the same distance and for the same length of time, each time, the same volume of air will fiow into the gun barrel each time the valve is opened, and the volume of air will be at a lesser pressure each time the valve is opened. Thus, as a constant volume of air of a continually diminishing pressure, flows into the gun barrel each time the valve is opened, the muzzle velocity of each successive projectile which is shot from the barrel will be materially less than the previously shot projectile. Thus, the gun is not accurate and is not, in effect, a repeater, even though the gun may be able to shoot more than one projectile. V

Another previously developed gun which claims to be, but is not a repeater, is constructed so that the control valve opens against and is closed by the pressure of air in the storage chamber, rather than by means of a spring, as in the construction described above, and uniform muzzle velocity of a plurality, of projectiles cannot be obtained. In this construction the hammer, which strikes the valve stem to open the valve against the air pressure has its throw mechanically stopped so that the air pressure inthe storage chamber alone is not relied upon tostop the hammer throw or absorb the momentum and energy of the hammer. Therefore, the valve will open substantially the same amount each time it isstruck by thehamm'er, and irrespective .of'the pressure of air'inthe storage chamber. Furthermore in this. construction the spring which actuates the hammer follows the hammer through its entire movement, even after it has struck the valve stem. Thus, when the air pressure in the storage chamber starts to close the valve, it must overcome the force exerted by the hammer spring, thus slowing down the closing operation and allowing such a great amount of air to go into the gun barrel that from a practical standpoint the gun cannot act as a repeater.. Still further, in this construction the heavy hammer and spring which are employed open the valve such a. great distance that even if a large storage chamber were provided, practically all of the air would escape therefrom on the first opening of the valve. However, even if the hammer weight and hammer spring rate were reduced so as not to cause this latter condition, the gun would not operate as a repeater because the muzzle velocity of successive projectiles which are. shot from the gun will drop considerably. As projectile muzzle velocity is a function of the air pressure and volume which is applied'thereto, and as the valve of this gun opens substantially the same amount each time it is struck by the hammer, irrespective. of the pressure in. the storage chamber, uniform muzzle velocity cannot be obtained, even though more than one projectile can be shot from a single air charge.

The gun of this invention incorporates, as do the guns shown in previously discussed patents, a control valve which is actuated and opened by a spring actuated hammer. The valve is normally held in its closed position, by the air; pressure in the storage chamber, although a very light spring is provided to hold the valve in its closed position when no air pressure is present in the storage chamber. When the trigger mechanism of this gun is actuated, the hammer spring throws the hammer forwardly toward the valve stem, but the spring does not follow the ham.- mer through its entire movement. Therefore, what might be termed a free-floating hammer is provided, which strikes the valve stem through the medium of an anvil so as to open the valve against the air pressure in the storage. chamber. The forward movement of the hammer is stopped almost entirely by the air pressure in the storage chamber and mechanical means are not relied upon to stop the hammer movement, as in certain of the previous constructions discussed. Therefore, the distance the valve opens will vary as the pressure in the storage chamber decreases. As the pressure in the storage chamber decreases, the valve opens further and fora greater length of time, to permit a greater volume of air to flow to the gun barrel for propelling the projectile therefrom.

As the muzzle velocity of the projectile is in effect a function of the air pressure and the time the valve remains open, or the volume of air which escapes into the gun barrel behind the projectile, and as the hammer weight and hammer spring rate are properly calibrated, the pressure of air and time the valve remains open are so coordinated as to produce a substantially uniform muzzle velocity. Furthermore, as the hammer spring is not acting against the hammer when the latter strikes the valve stem or anvil, the valve can be'quickly closed by the air pressure in the storage chamber and the force exerted by the spring need not be overcome before the valve can be closed. Thus, the gun of this inventionis constructed and calibrated in such a manner as to enable a plurality of projectiles to be propelled therefrom, after the air chamber has been charged, at a substantially uniform muzzle velocity, thereby, for the first time providing an air gun. which is actually of the repeater type; From actual tests conducted with the gun of this invention, it has been found that the muzzle velocities of a plurality of shots, whether they be 10, 25. 50, etc, will not vary over ten percent and generally the variation between the muzzle velocities of the shots will be less than five percent. With guns of the previously developed type, as described before, if more than one shot is obtained, from a single air charge, the variation in muzzle velocities of the projectiles. is. extremely high, and several shots can be obtained only if the gun is pumped an excessive and impractical number of times, so as to provide a very high air pressure in the storage chamber.

It istherefore an object of this invention to provide a hand-carriable, repeating type pneumatic gun, of the aforementioned type, which will fire a plurality of projectiles, from a single air charge, at a substantially constant? velocity.

It is a still further object of this invention to provide a novel and. simple mechanism for a pneumatic gun of the aforementioned type, which will permit a plurality of projectiles to be shot at a substantially uniform muzzle velocity.

It is a still further object of this invention to provide a pneumatic gun. of the aforementioned type, which is more durable in use, rugged in construction, and more accurate in operation than any pneumatic gun heretofore known.

These and other objects of this invention will become. apparent from the following detailed description, taken in conjunction with the accompan-ying drawings, in which:

Fig. l is a fragmentary longitudinal sectional view through a pneumatic gun embodying the features of this invention;

Figs. 2 to 7 inclusive are respectively cross sectional views taken on the lines 2-4, 3 -3, 4-4, 55, 6-45 and 'i--'.' of Fig. 1;

Fig. 8' is a fragmentary side elevational view of the breech end of the gun;

Fig. 9 is a longitudinal sectional view through the construction shown in Figure 8;

Fig. 10 is a cross sectional view taken on the line lii--i 6 of Figure 9;

Fig. 11 is a detail perspective View of the hammer shown in Figure .9;

Fig. 12 is an elevational view of the breech end of the gun;

Fig. 13 is a fragmentaryperspective View of a part of the firing valve assembly;

Fig. 14 is a fragmentary longitudinal sectional view through a pneumatic gun, illustrating a further embodiment of this invention;

Fig. 15 is an enlarged sectional view of structure illustrated in Fig. 14, taken along line |5-|'5 thereof;

Fig. 16' is an enlarged sectional view of the structure illustrated in Fig. 14, taken along the line i6- |ii thereof;

Fig. 17 is an enlarged sectional view of structure illustrated in Fig. la, taken along line l'li'l thereof; and

Fig. 18 is an enlarged sectional view of structure illustrated in 1%, taken along line 18-43 thereof.

Referring now to the dr wings and more particularly to Figs. l-13 inclusive, will be seen that a pneumatic gun of the rifle type, which simulates in appearance an orthodox, well-balanced firearm, is provided. It will be understood, however, that. the, mechanism of this invention may be employed in pneumatic pistols or other types of weapons of a different design from that the the the the the the illustrated and described. The pneumatic gun comprises a stock H, and a frame I 2, suitably secured to the stock by any suitable'means, such as screws I3. The frame I2 comprises a barrel I4, a main storage chamber I5 and'a secondary storage chamber I6, communicating with the main chamber I5 through a port H.

The barrel I4 has a bore of sufficient size to receive shot of either the ball or pellet type, and this shot may be inserted into the breech end of the barrel through a suitable opening 58. In Fig. l of the drawings, a pellet type shot is is illustrated in the breech end of the barrel and this shot is preferred in instances such as target shooting, where maximum accuracy is required. The pellet I9 is formed with a relatively thin skirt 29 at the trailing end and this skirt is normally flared outwardly. The maximum normal diameter of the skirt 20 exceeds the diameter of the bore and is contracted when inserted into the bore to insure circumferential contact between the skirt and the inner surface of the bore. The skirt is relatively thin and the pressure of propelling air introduced into the barrel behind the pellet tends to expand the skirt outwardly against the inner surface of the bore to provide a seal. As a result, leakage of air under pressure past the pellet is negligible and the pellet is accurately guided along the barrel. It will further be noted from Figs. 1 and 5 of the drawings, that the usual front and rear sights 2i and 22 respectively, are mounted on the muzzle and breech ends of the barrel.

The storage chamber I5 i positioned below the barrel I4 and between the barrel and secondary 1- chamber I6. The breech or rear end of the chamber I5 is connected to a tubular compart ment or chamber 24, through the front wall 24' thereofjby means of a bore 25, having the front end portion thereof enlarged to provide a pass'ageway 26. A vertical passageway 21 connects the passageway 26 intermediate the ends thereof, to the barrel I4 at a point ahead of the pellet receiving opening I8, and enables air under pressure to flow from the storage chamber I5 to the barrel, rearwardly of the pellet I9, in a manner which will be hereinafter described.

The flow of air under pressure from the storage chamber I5 to the barrel I4 is controlled by a valve 28, comprising aplunger 29 and ,a valve member or pad 30. The pad 30 is suitably secured to the rear end of the plunger 29 and is formed of a wear-resisting deformable material such as, for example, rubber, syntheticrubbenor some other equivalent material. The plunger 29 is slidably supported in the rear end of a handoperated compressor assembly 32, so that the pad 30 will normally engage the front face of the tubular compartment wall 24f and close the en trant endof the passage 26 That is, the front face of the tubular compartment wall 24' pro:- vides a valve seat 3| for the valve member or pad 39. Owing to the pliable nature of the material from which the valve member 30 is made, the latter intimately engages the seat 3I and assures a tight seal, regardless of irregularitie in the adjacent surfaces of either the valve seat or valve member. It will also be noted that the valve 28 is constructed so as to enable practically instantaneous opening thereof, in a manner which will be hereinafter described, to admit fluid under pressure to the gun barrel. v

While any suitable type of compressor may be provided for compressing air in the storage chamber I5, the compressor 32 which is illustrated; forms a unit with the gun andis manually operable :to supply fluid under pressure to .the storage chambers I5 and I6. The compressor 32 comprises a cylinder 33 and a piston assembly 34, which is slidably supported in the cylinder. The front end of the cylinder is closed by a cap 35, which is removably secured in place by asset screw 33. The cap 35 is centrally apertured so as to slidably receive .a rod 31. The rear end of the rod 31 is connected to the piston assembly 34 for universal movement relative thereto, and the front end of the rod 31, outwardly of the cap 35, is provided with a hand grip or knob 38. r

Y he piston assembly 34 comprises a sleeve 39, having a sealing washer frictionally engageable with the wall'of cylinder 33 and securedto the rear end of the sleeve 39 by a stud 4|, having a passage 42 therethrough registering with.- the bore of the sleeve. The-rear end portion of the rod 3'! is reduced at 43 and a head 44 is formed on orconnected tothe reduced portion 43 at the rear thereof. The head 44 isslidably supported in the bore" of the sleeve 39 and'is conical in shape, so as to act as a valve member for closing the stud passageway 42. The extentof sliding movement of the head or valve member 44 is limited by a pin 45 threaded into a tapped'o'pen ing in the sleeve 39, adjacent the front end there of. The inner end of the pin 45 projects into the bore of the sleeve 39 between the head or valve member 44 and'the shoulder 46 on the rod 31, formed by the reduced portion 43. 1

The rear end of the cylinder 33 is formed :with a rearwardly projecting nipple portion 41, having a passageway 48 therethrough, aligned with the passageway 42 on the stud 4| and normally closed by a check valve 49. The check valve includesa' valve stem 50 which is housed in-a tubular 'cage 51. The front end'of the cage'5I is internally threaded "for threadably engaging the nipple 4! and an annular shoulder 53 extends in-' wardly from the peripheral wall of the cage 5i, at a point axially rearwardly from the nipple 4-1; The front end of the valve stem 59 extends into the nipple passageway 43 and the rear end of the stemprojects through the annular shoulder 53. An enlargement or valve head 54 is provided on the valve stem SUintermediate the ends thereof, and a washer 55 of yieldable material, is posi} ti-oned on the valve stem, in an abutting relationship with'the front'face of the enlargement '54, for contact with theadjacent rearend of the nipple 41, 'to close the passageway 48. A 'co il spring'56 surrounds the valve stem 50 between the enlargement 54 and-the annular cage shoulder 53, for normally holding the valve 49 against the rear face of the nipple in' a closed position. The front end portion of the valve stem Ellis tapered so that air displaced by the piston assent-"- bly may be discharged through the passageway 48, as soon as the valve 49 is opened against the action of the spring 56. g v I Referring now to the operation of the compressor assembly 32 and assuming that the parts thereof are in the position shown in Fig.1 of the the piston assembly 34, air'from the atmosphere is free to pass through the sleeve 39, around the head 44 and through thepassageway 42, into-the cylinder 33, rearwardly beyond. thepiston. In this connection, it. will be noted that the head 44. is formed with. a plurality of flutes 4.4" enabling the air to. flow around the head 44.. After the rod 31 is moved to its forwardmost position, it is pushed. inwardly and the. initial rearward movement of the rod engages the head 44 thereof with the forward end of the. stud 4 I so as to close passageway 42. In this manner, air is trapped in the cylinder rearwardly of the piston assembly 34 and continued. rearward movement of the rod 31 imparts a corresponding movement to the piston assembly so. that the air is compressed in the cylinder' rearwardly of the piston. Thev air under pressure actuates the check valve 49, when the force thereof exceeds the force of the. spring 56. and the check valve is. opened permitting the fluid under pressure to pass. into the storage chambers I and I6. At the end of the rearward stroke of the rod 31, and piston assembly 34, the check, valve 49 closes, trapping the compressed air in. the storage. chambers.

The compressor assembly 32 enables the storage chambers I5 and I6 to be replenished with air under substantial pressure, in a minimum length of time and; with very little or no loss of air due to. leakage. It will also be noted that provision is made for maintaining the rod 31 in its rearwardmost.v position when it is. not in use. As is shown in Figs. 1-3 inclusive, a key 58' is formed on the rod 31. and a corresponding slot 59 is formed. in the cap 35. The arrangement is. such that forward movement of the operating rod is prevented until the key 5.8 is aligned with the slot 59.

The: valve plunger 29, previously described, is

held in a position at the rear end of the cage, so 1 that the pad- 30 thereon engages the valve seat 3i, by means of a light coil spring 62, which is disposed in the cage 5i. between the shoulder 53 and valve plunger 29. The spring 62 is provided for holding the valve pad. 3.0 in its closed position with. respect to the passageway 26, when. there is no, fluid pressure.- in the storage chambers, but when fluidv is compressed in. the chambers it. provides the major force. effecting the closing of the valve, and the force exerted by the spring 62 is negligible as compared to the force. exerted by the. compressed fluid.

Forward movement of the valve 28', to an open position, connects the storage chambers I5 and I6 to; the gun barrel. I4, rearwardly of the positioned projectile I9, for propelling the projectile outwardly through the barrel. In order to open the valve 28 the desired amount, as will hereinafter appear, a plunger or stem 66' is provided, which extends through bore and is' slidably supported in the. wall 24' of the compartment 24. The length of the plunger or stem is such that the, rear end portion thereof projects into the hollow interior of. the compartment 24 and the front end portion thereof extends axially through thefenlarged passageway 26 into abutting en.- gagement with the. valve pad 30. A head BI. is formed on the plunger or stem 60', intermediate the ends thereof, and is positioned in the passageway 26 The head 6| acts as a stop to limit rearward. movement of the plunger or stem 60 and serves as a seal. to' prevent the escape of air fromv the passageway 26 into the compartment 24.

The rear end portion of the plunger 60', which projects into the interior of the tubular compartment 24, is engaged by the front face of an anvil 84, which is slidably disposed in the compartment 24 and is secured to the front end of a rod 65. The rod 65 extends axially of the compartment 24 and the rear end thereof is slidably received in a recess or bore 66, formed in a plug or closure 61 in the rear end of the compartment 24. The length of the recess or bore 66 is greater than the distance between the anvil 64 and the adjacent back face 68 of the compartment wall 24' so that the rod will not become disengaged from the bore or recess 66.

The anvil 64 is adapted to be struck and actuated by a sleeve-like hammer 69, which is slidablymounted on the rod 65 and has a head portion 10 formed at the rear thereof. The hammer 69 is actuated or thrown forwardly toward the anvil 64, by a coil spring I I, which surrounds the rod 65 between the hammer head Ill and the closure 61. The coil spring is constructed so that when it has expanded to its full length, in moving the hammer toward the anvil, it will become disengaged from the back face of the hammer prior to the engagement of the hammer with the anvil. It should, furthermore, be noted that the hammer is in effect, of the free floating type, that is, it is thrown forwardly by the spring II and moves out of engagement therewith prior to striking the anvil 64, and is guided during its axial movement. by the rod 65 and the. wall of chamber 24. The forward motion of the hammer 69 is stopped almost entirely, and for all practical purposes by the storage chamber fluid pressure, acting, against the valve 28, after the same. has been opened by the momentum of the. hammer. anvil, and valve stem or member 60. This is of considerable importance, as will hereinafter more fully appear. .The hammer 69 is held in its rearwardmost position, wherein the spring II is compressed, by a trigger sear I2 pivotally mounted on the frame I2, below the compartment 24, by a pin I2, for swinging movement about an axis extending, at right angles. to the path of travel of the. hammer 69. The swinging end. of the sear I2. is. bifurcated and onefurcation I3 thereof projects upwardly through a slot .14 in the adjacent wall of thecompartment24, for engaging the front. face of the hammer headv Iii, when the latter is in its retracted position, as shown in Fig. 1.

The scar 121s operated by a trip lever 15, which is pivotally supported rearwardly of the sear on a pin I6, mounted in the frame I2. The trip lever I5 has an arm portion '11 which extends forwardly between the furcations of the sear 72, as well as adependingarm- !8, which projects through a slot I9 in the gun frame. I2 for engagement with a trigger 80. The trigger is supported for sliding movement on a trigger guard 8|, which is suitably secured to. the under side of the gun stock: I I by screws 82. The trigger is provided with a lug 83, which projects upwardly through an elongated slot 84 in the gun stock to a position in advance of the arm I8 on the trip lever '15. A suitable leaf spring 85 is provided which tends to swing the trip lever '15 in a clockwise direction, as viewed in Fig. l, with the result that the trip lever arm 11 holds the furcation I3 of the sear I2 in the path of 9 the head 10 of hammer arm 18'coacts with the lug 83 on the trigger to hold the latter in itsQf-orwardmost position.

The hammer 69 is retracted to its cocked position by a plugSB supported on the gun frame at the breech end of the barrel, for sliding movement fore and aft thereof. The top wall of thetubular compartment 24 is formed with a slot 69, and the trip lever.

81 extending rearwardly from the breech of said the slot 81. The block 85 is then slipped on the top wall of the compartment 24 with the opposite longitudinal edge portions of the slot 8'! respectively engaging in the grooves 88 in opposite sides of the block. The plug 51 is then inserted into the rear end of the compartment 24. I

A stop or lug 89 is secured to the under side of the block 86 in a position to engage the front side of the hammer head 19, upon rearward movement of the block, so as to retract the hammer 69 and compress the hammer spring H. The block 86 is moved rearwardly by an inverted substantially channel-shaped cap 90 extending longitudinally of the gun frame, tonormally'conceal the shot-receiving opening l8 and the slot 81. Side flanges 9| of the cap extend downwardly along opposite sides of the tubular compartment 24, and respectively slidably engage in suitable ways formed by strips '92 fixed to opposite sides of the compartment 24. The cap 99 provides a convenient grip to enable sliding of the block 86, and is connected to the block bya screw 93. The screw 93 threadably engages the cap 90 and projects into a slot 94'formed in'the block 86. The front end of the cap 99 projects over the projectile opening l8 and abuts a shoulder 91 formed on the breech end of the barrelp-"I'he shoulder 91 serves to locate the cap 99, in its forwardmost position wherein the block 86 engages a stop 98 formed by the rear end of the barrel.

' The block 89 also operates a positioning pin" 99 which is slidably supported in the barrel at thebreech end thereof and which has its rear end fixed to the block by any suitable means. The length of the positioning pin is such that when the block 86 is in its forwardmost position against the stop 98, the front end of the pin extends forwardly, beyond the passage 21, so as to position the projectile IS in the barrel ahead of the passage 21. The forward end )0 ofthe pin is reduced in diameter so as not to interfere withthe flow of air from the passage 21into' the barrel behind the projectile. The shot receiving opening I8 is so located that when the block 86 is in its retracted position; the front end of the,

positioning pin 99 assumes'a position to the rear of the opening so as to permit a projectile 19 to be inserted into the barrel through the opening I8, Other means such as will be hereinafter described, may be provided for loading and posiadjusted priorto the above operation to align the key 58 on the rod with the recess 59 in thecap 35, so that the piston assembly 34 may, in

chambers.

10- chambers, the first step*required to place the gun in an operative or firing position is to intro-' duce air into storage chambers l5 and [6. This may be'readily accomplished by placing the gun in an inverted vertical position with the knob: or grip 38 resting on the top of a table or other suitable support and by reciprocating the gun with one-hand whileholding the knob 38 against the table'with the other hand. It will, of course, be understood that the rod 3'! is angularly effect, be reciprocated in the cylinder 33. As the piston assembly 34 is, in effect, moved toward thevalve 49, air is compressed in the cylinder 33 and when the pressure of the air exceeds the force of the spring 56, the valve is opened per-- mitting air under pressure to escape through the passage 48 into the-storage chambers I5 and 1 l6. 7 On the other hand, when the piston assembly 34 is in effect moved-in a direction away-from the valve 49, the latter is closed by the spring 56 preventing the reverse flow of air through'the V passage 48. The above pumping action is continued until the desired air pressure is obtained in the storage chambers,-and while this pressure may vary considerably-, nevertheless, it will be assumed that a pressure .of approximately 450 pounds per square inch is obtained in the storage The gun may then be-cocked by moving the cap 90 rearwardly from the position thereof shown in Figure 9 of the drawings. movement of the cap 90 imparts a corresponding movement to the block 86andthe positioning pin'99. As the block86 moves rearwardly the projection or screw 89 engages the head 10 on the hammer 69 .and slides the latterrearwardly along the rod 69 As the head 10 passes overthe t'o-return'. the furcation 13 to a position in ad-- vanceof thehead 10 where it actsasastop to hold the hammer in its cocked'position .In the rearwardmost position of the block 86 the positioning pin 99 is Withdrawn to a position wherein-the front end 199 assumes a position in.

the barrel l4 rearwardlybeyond the opening. l8,

and the vlatter is uncovered by the cap 90. A. shot such, for example, as a pellet I9, is inserted into the'barrel [4 through the opening [8, and

: the'cap 90 ismovedforwardly until the front. The block" end thereof abuts the shoulder 91. B6 is, of course, moved as a unitwith the cap,

and the pellet I9 is advanced by the positioning pin 99 to a' position in the barrel l4 in advance of the passage'fl.

l wardly the lug 83 cooperates with the-arm 18 on" Upon completion of the above operation the gun is in condition forfiring and this may be accomplished by sliding the trigger in a rear-.

ward direction. As the trigger is moved rearthetrip 15. to rotate the latter in a direction to again swing the sear l2 downwardly against the action of the spring and'disengages the furcation I3 from the head 10 on the hammer 69.

' Asaresult, the spring 1| throws the hammer 69 forwardly against the anvil 64, and the force of the blow on the anvil istransmitted to the Rearward off the seat 3| and permit air under pressure from the storage chamber l5 to escape into the gun barrel I4 behind the pellet l9. Thus the pellet I9 is propelled through the barrel at a very high velocity depending upon the amount of air under pressure admitted to the barrel for a given static pressure in the storage chambers.

As has been previously pointed out, there are several factors which affect the operation of the gun and which make the difference between a practical repeating type gun and a gun which, although capable of firing several shots from a single air charge, is not a repeater. These factors include such things as the weight of the hammer, the K factor or stiffness coefficien't of the hammer spring H, the manner in which the hammer is actuated by the spring II and the manner in which the forward momentum or energy of the hammer is stopped or absorbed. Certain of these factors, such as spring K factors and hammer weights, may vary in accordance with the number of projectiles it is desired to shoot from a single air charge, the capacity of the storage chambers l5 and IS, the pressure of air in the storagechambers, etc. A specific example of the relationship of these various factors will now be set forth, but it is to be understood that these factors may be varied within predetermined limits, in accordance with the above mentioned conditions. In the following example, the gun is constructed in the following manner: the hammer spring H has a stiffness coefficient or K factor of 3.12 poundsper inch; the spring 62 has a stiffness coefficient or Kfactor of 2.81 pounds per inch; the spring H is compressed before firing, from its free length, a distance of 1 inches and is at a free length afterfiring or actuating the hammer; the spring 62 is initially compressed from its free length before firing, a distance of 1 /5 inches; .thepressure of air in the storage chambers l5 and 16 is 450 pounds per square inch; the weight of the hammer 69 is .06 pound, and the mass is therefore .06/32 slug; the total .weight of thevplunger or valve stem 60, anvil 64 and rod 65 is ;.0467 pound, or amass of .0467/32 slug; and the face area of the plunger or valve stem 60' .is -'.0472 square inch. From this data the amount of compression 'of spring '62, from its free '-length to its -length after firing, can be calculated, and 151.658 inches. The distance the firing valve 28. opens is, therefore,

the difference between the final compression of.

the spring '62 and the initial compression thereof, or .064 inch. These are, of course, theoretical figures, but from actual tests run on a gun constructed in accordance with the above factors, it was found that the firing valve 28 opened .062

inch.

From the above data, the total time the firing valve remains open can also be calculated, and with a storage chamber pressure of 450 pounds per square inch the firing valve, will remain open .00445 second. Knowing thejface area of the skirted end of the pellet in the barrel and the mass of the pellet in the barrel, the time the firing valve remains open, and the fluid-pressure in the storage chambers l5 and I6, the muzzle velocity of each of a plurality of pellets, which are shot from a single air charge in the storage chambers, can be calculated. If the gun.

is fired twelve times, without recharging the storage chambers 15 and 16, the pressure in the storage chambers, willdrop, and as the pressure decreases, .the spring actuated hammerr69 will open the valve 28, a progressively larger amount.

12 Due to the fact that the mass of the hammer 69 and the amount of compression of the spring ll remain constant at all times, and due to the fact that there is nothing to stop the forward throw or momentum of the hammer 39 and absorb the energy thereof, except the fluid pres sure in the storage chamber, and the spring '62 which has a negligible constant effect on the distance the firing valve 28 is 'op'en'ed,.the length of time that the firing valve 28 remains open progressively increases as the pressure in the storage chambers l5 and I6 decreases. Thus, from both theoretical calculations and from'the actual measurements of muzzle velocities of projectiles, there is found to be only a total variation in the projectile muzzle velocities between the first and twelfth shot, of less than five percent, and generally this variation will be less than three percent. If it is desired to shoot, for example, twenty-five projectiles from the single air charge in the storage chamber, this can be readily done by varying "the hammer weight and spring '00- efiicient. The muzzle velocities will, of course, unless the capacity of the storage chambers or the pressures therein are increased, be lower than when only twelve shots are being fired, but the variationbetween the first and twenty-fifth shot will be very, very small and substantially the same percentage as set forth above. As a matter of fact, as many as eighty to a hundred projectiles have been shot from a gun of this invention, without any substantial variation in the muzzle velocities of the projectiles. It is extremely important that the K factor of the spring and the hammer weight be of the proper amounts and in the proper relationship, in order to obtain the desired results. I

For example, with the gun of this invention it has been found from actual tests, with afiuid pressure in thestorage chambers l5 and I6 of approximately .350 to 360 pounds per square inch, that the bestresults are obtained with a hammer weight of approximately .04 pound and a spring ll having a K factor or stiffness coefficient of approximately 2.9 pounds per square inch. With this hammer Weight andspring K factor, there was only, a difference in muzzle velocities, between the first and tenth .Iproj'ectile, of seventeen feet per second. That is, the muzzle velocity varied from 5'78 feet per second to 561 feet per second. If the gun were constructed with a hammer of the same weight as before, but with a spring having a greatly increased K factor, such as nine pounds per square inch, the variation in pelletmuzzle velocity, between the first to the tenth shot would be 140 feet per second, or a drop from 557 feet per second to 417 feet per second. Similar results are obtained if the hammer weigh-t is materially increased or if both the hammer weight and the K factor of the forward momentum of the hammer andreverse its motion, {so as topermit the valve to be closed andas a result a large percentage of the air in the storage'chamber will flow into the gun. barrel behind the shot, and there will not be enough air left in the storage chambers to fire mentum or forwardthrow of the hammer tosuch an extent that the time the firing valve re '13 mains open will be too much to permit a plu-. ral-ity of successive shots to be firedat substantially the same muzzle velocity.

It will, therefore, be seen that the hammer Weight and the K factor of the hammer spring are extremely important in the construction of an air gun of the repeater type. It will further-i more be understood that the gun must be constructed so that the firing valve will only remain open a small and predetermined amount of time, each timeit is struck by the hammer and plunger. arrangement. This time will, of course, vary in accordance with the pressure in the storage chambers I and I6, but no one heretofore has ever developed an air gun in which the length of time the firing valve remains open is controlled accurately and in such a manner as to produce the results set forth above. This failure in the past has resulted not only from a failure to obtain the proper relationship between the hammer weight and spring K factor, but alsobecause no one in the past has provided an air gunin which the air pressure in the storage chamber is relied upon almost entirely to absorb the energy and momentum of the hammer and cause the firing valve to close, and because no one in the past has constructed a gun in which the hammer is free floating or engages the valve stem or. plunger while being free of the hammer spring If the hammer spring followed the hammer throughout its entire forward movement, its compressed energy would have to be overcome by the air pressure in the storage chamber before the direction of movement of the hammer could be reversed. The length of time for closing, the valve 28 with such a construction would be so long that the aforementioned repeating conditions could not be obtained. It should also be appreciated that the gun of this invention is of the hand-carriable type, and. does not, require the use of a mechanically driven compressor or the like. Thisgun thus provides a simple, relatively inexpensive and eflicient repeating air gun which, after the air chamber has once been charged, can fire a plurality of projectiles at substantially the same muzzle velocity, and which at the same time can be easily carried by the user to any desired place, withoutthe necessity of carrying along a separate compressor unit.

Slight variations in the range of muzzle velocities of the projectiles may be obtained by varying the kinetic energy of the hammer 69. This may be easily accomplished by a user of the gun with the construction illustrated in Figure 11 of the drawings, wherein it will be noted that the head on the hammer 69 is formed with axially spaced shoulders IM and I 02. The ar rangement is such that in one rotative position of the hammer 69, the shoulders IOI are 1'8- spectively engaged by the block 86, and the sear I2, while in another rotative position of the hammer 69, the shoulders I02 are positioned for engagement by the block 86 and sear I2. When the shoulders IUI are in operative relationship to the block and sear, the spring 'II is compressed to a greater extent than when the shoulders I02 are in their operative position, so that the hammer 69 is moved forwardly with a greater velocity. Thus the head 30 on the valve member 28 is moved a greater distance away from the seat 3|, and the time the valve 28 remains open is correspondingly increased. However, thedifference inlength of 'time the valve will remain'open, as compared with the length of timepreviousl'y'discussed is so slight that it will not affect the repeating characteristics of the gun. The primary purpose of the hammer adjustability feature is to permit the projectiles to be shot in a lower velocity range, which may be desirable with certain types of shooting, such as indoors, or the like. The two muzzle velocity ranges permitted with this construction are, furthermore, not widely separated from each other.

In instances where a hammer having axially spaced shoulders is employed, the rear end of therod 65 projects through the breech plug 61, and is polygonally shaped in cross section. As shown in Figure 9 of the drawings, a sleeve I03 extends through the breech plug for slidably receiving the rear end of the rod, and relative rotation between the sleeve and the rod 65 is prevented by a set screw I94 carried by the sleeve, as can be clearly seen in Fig. 10. A control knob I05 is positioned on the rear end of the sleeve Hi3 for convenient manipulation by the operator, and is secured to the sleeve by a set screw I06. The arrangement is such that rotation of the knobv I05 imparts a corresponding rotation to I the rod to locate one or the other of the sets of shoulders IBI and I02 on the hammer in operative position with respect to the block 86 and sear 12. Thus, the projectile muzzle velocity range may be varied by merely adjusting the knob I05.

The modified air gun construction illustrated in Figs. 14 through 18 is similar in many aspects to that previously described and parts of this construction generally similar to parts in the previous construction are indicated by double primed numbers corresponding to those of the previous embodiment. The gun comprises a stock I I" and a frame I2" which is secured to the stock in any suitable manner such as by means of screws I3". The frame comprises a barrel I4", a main storage chamber I5" and a secondary storage chamber I6" communicating with the main chamber through a port I1", The storage chamber I5" is connected to the tubular compartment or chamber 24" in the same manner as in the previous embodiment. The flow of air under pressure from the storage chamber I5 to the barrel I4" is controlled by the valve 28", which is substantially the same as that previously described.

The compressor 32" illustrated in this embodiment of the invention is of a slightly different form than that previously described, but it still forms a unit with the gun and is manually operable to supply fluid under pressure to the storage chambers I5" and I6". The compressor 32 is generally similar to that illustrated and described in the copending patent application of Charles F. Lefever for improvements in Pressure Producing Device for Pneumatic Guns, Serial No. 32,880, filed June 14, 1948, and includes a cylinder III having a piston assembly I I3 slidably supported therein. An annular shoulder or stop I I5 isprovided in the cylinder I I I, intermediate the ends thereof, and the shoulder is centrally apertured at 1. The rear end of an operating rod H9 is threadably connected to the piston H3 and has a longitudinally extending passageway I2I therein, which is enlarged.

. a pin I21. The forward end of the rod passage way "I communicates with the cylinder III through a vertically extending passageway I3I.- The front end of the cylinder Ill is closed by means of a cap .I35 which is threadably con nected with a sleeve-like member I3i, which in turn is threaded into the forward end of the frame I2 at I33. The forward end of the cylinder I It fits into the rear end portion of the sleeve member I3? and is secured thereto in any suitable manner such as by soldering, or the like. The cap I35 is centrally apertured so as to slidably receive the rod I if) and a ball-type detent MI .is provided in the cap I35 for engagement with an annular groove t lt, adjacent the forward end of the rod I it, so as to releasably hold the same in its innermost position. A foot engaging member M5 is "ivotally connected at one end to an enlargement or head it? on the forward end of the rod Ila outwardly of the cap E35. Movement of the rod i It and piston i I3, inwardly and outwardly, is limited by the cap I35 and the cylinder shoulder H5.

Rearwardly of the cylinder shoulder -I I5 a check valve Ifii is provided which includes a valve stem I53 and a valve head I55, mounted on the stem, intermediate the ends thereof. The rear end of the valve stem I53 is slidably supported in an aperture I57 of a second cylinder shoulder or abutment IE9. A coil spring 'IBI is mounted on the valve stem its between the cylinder shoulder I59 and the valve head I55, so

as to resiliently hold the valve head I55 in sealing engagement with the back'face of the cylinder shoulder IE5, and thereby normally close passageway II'i against the flow of air therethrough. When it is desired to compress air in 2 the storage chambers l5 and 16" the gun is placed in an inverted vertical position, so that the user can place a portion of his foot on the rod foot-engaging member I lii. When the body of the gun is pulled upwardly away from the held member I45, atmospheric air in the forward end 'of' the cylinder III passes through the rod passageways I3I and IZI, forces the ball I off its seat and flows through enlarged passageway I23, where it is stopped by check valve I5I. When the body of the gun is moved downwardly, air is compressed behind the piston II3, as the ball I25 will immediately be seated by the trapped'air. When suiiicient pressure has been built up, the valve iiii will be unseated so as to permit the air to flow into the cylinder II I behind the valve. The air in the rearward por tion of the cylinder can then flow through a cut out portion or notch I65 in the wall of the cylinder I l I, into the annular space between the cylinder wall and the frame of the gun, and thence down through port ll and into the secondary storage chamber It". The compressor unit enables the storage chambers I5 and I8" to be charged with air under suitable pressure in aminimum length of time and with practically no leakage. The forward end of the cylinder I I I is replenished with atmospheric air in any conventional manner, such as by air leakage between rod H9 and cap I and/or through suitable cylinder openings.

The forward end of the secondary storage chamber Is" is closed by means of a cap It? which is centrally apertured to receive a headed pin I 6.9. The pin I59 has, adjacent its forward endQindicia thereon in the form of difierent colored bands or stripes I'M. A plunger or piston I13 is connected to the rear portion of the pin IE9 and a coil spring H5 extends between the cap I61 and the piston I1 3. When sufiicient izontal plane, as the barrel I l".

pressure is built up .in the storage chambers I5" and It, the piston I13 will be moved forwardly thereby against the action of the spring I15, so as to make the stripes or bands Il I visible from the exterior of the gun. The spring I15 is so calibrated that when the desired pressure in the storage chambers is reached, the rearwardmost band or stripe I'll will be visible, and when the pressure in the storage chambers is below the desired or necessary amount, the bands or stripes, or at least the rearwardmost stripe, will not be visible to the user. In this way, a user who has charged the gun and fired only a few shots therefrom, before putting the gun away for a con. siderable period of time, will not, when he picks the gun up again, be in doubt as to whether or not there is sufficient air pressure in the storage chambers to shoot the gun in the desiredmanner; The valve plunger 29", as previously described, is slidably supported in the rear portion of the compressor cylinder III in generally the same manner as previously described, and is yieldably held in a position at the rear end of the cylinder so that the pad 35 thereof engages the valve seat 3i", by means of the light coil spring 62". The spring 62 acts in the same manner as in the previous embodiment. In order to open the valve 28" and connect the storage chambers to the gun barrel, rearwardly of a positioned projectile I9, the plunger or stem 66", having an enlarged head GI", the anvil $4", rod hammer G9" and hammer spring 'H" are provided in exactly the same manner as previously described. The hammer 5.8" is provided with the enlarged annular shoulder it! at the rear end thereof for engagement by the bifurcated trigger sear "I2" which is adapted to be actuated by a trigger mechanism iSI of any conventional or suitable type. The valve 28 is opened by the engagement of the hammer with the anvil, after release by the trigger mechanism, in substantially the same manner as previously described.

The rear end of the barrel I4" extends into and is connected with .a breech block I83 which in turn is connected with the frame of the gun in any suitable manner, above the compartment 24". A magazine I85, in the form of a cylindrical passageway in the block I 83, is provided adjacent to and in substantially the same hor- A magazine tube I81, in which a plurality of pellets I9 are stored in end to end relationship, has its opened end inserted into the forward end of the magazine its and its closed end connected with suit able bracket means (not shown) on the barrel, whereby the tube may be easily removed from the magazine for refilling. The rear end of the magazine communicates with the barrel I4" through a transversely extending recess or notch its in the breech block I83, as is generally illushated and described in the copending patent application of Charles Lefever for improvements in Loading Mechanism for Pneumatic Guns, Serial No. 39,397, filed July 19, 1948, and now Patent Number 2,594,185. The recess or pocket I93 has a width slightly greater than the length of one of the pellets I9" and the breech end of the barrel- It" opposite the recess I93 is slotted at Is! to receive one of the pellets.

The pellet in the magazine, immediately adjacent to the rearmost pellet therein is held against movement toward the recess I93 by means of a pin I91, which is slidably supportedin a. vertical bore. formed in the top of the breech block E83 and positioned to extend into the delivery end of the magazine at a point to engage in the groove formed between the head and skirt portions of the aforementioned pellet. The upper end of the pin I9! is secured to a transversely extending leaf'spring 199, which has one end secured to the breech block by any suitable means such as a screw 2!, so that the leaf spring normally holds the pin in the vertical bore above the magazine. The leaf spring J99 is actuated, so as to move the pin downwardly into the magazine, by means of an arm member 203. The arm 203 is pivoted atits front end to the breech block i 83 by means of pin 205 and the rear portion of the arm is slotted to provide two furcations 20'! and 209; An angle shaped projection 2|! extends downwardly from the arm furcation 201 into the breechblock recess I93 for the purpose of transferring pellets from a position in the recess, at the delivery end of the magazine, to a position within the breech end of the barrel M.

An inverted, generally channel-shaped slide member 2| 3 is slidably connected to the upper portion of the-gun frame |2"'by any suitable means so as to normally cover the breech block I83 and arm 203. A cam 2| 5 is connected to one of the vertical side wall portions of the slide 2 l3 and is adapted, when the slide is pushed to its forwardmost position, to engage a cam surface 2 l1 formed on the outer edge of the arm furcation 200, so-as to normally hold the arm in such a position that the'downwardly extending projection 2 thereof is disposed laterally outwardly of the magazine I85. A hairpin typespring 2I9 is connected between the arm 203 and the breech block I03 for urging the arm projection 2 towards-the barrel, when the slide 2! 3 is pulled rearwardly.

The'upper wall of the compartment 24" is provided with a longitudinally extending slot 2 IS in which is slidably mounted a block 22!, which is connected to the slide -2|3 by means of screw 223. The block 22! is provided with a downwardly extending pin 225, which is disposed forwardly of the hammer shoulder so that when the block moves rearwardly it will move the hammer shoulder 10" rearwardly beyond the trigger sear 12'', in order to cock the gun. Projecting forwardly from the block 22! is a pin 22? which is slidably received in the rear end of the barrel M". The forward end of the pin 22! is tapered and reduced in diameter at 229 and positions a pellet l 9" in the barrel ahead of the compressed air vertical passageway 21'', as will be hereinafter described. Connected to the pin 221 intermediate the ends thereof,is a plate 233, the forward portion of which is notched or cut back to provide a furcation 235. When the slide 213 and block 2Z| are in their forwardmost position, after for example, a projectile has been fired, and it is desired to load and cock the gun, the forward end of the barrel is tilted upwardly and as the downwardly extending projection 2 of the arm 203 is disposed laterally outwardly of the delivery end of the magazine, the rearmost projectile in the magazine will drop rearwardly into the breech block recess ms. The pin I91 will prevent the adjacent projectile in the magazine from dropping into the recess, due to the fact that it is pressed downwardly by the arm 203. The projectile will be properly positioned in the recess I93 by the furcation 235 on the forward end of the plate 233.

' When the slide 2I3 is pulled rearwardly the plate 233, pin 22'! and block 22! will move rearwardly, as well as the slide cam 2l5. The hairp 18 spring 2l9 will then cause the downwardlyextending projection 2 to sweep across the recess I93 and position the pellet in the slotted portion IQ! of the barrel. At the same time, the downwardly extending pin 22-5 on the block 22l will move the hammer shoulder 10" past the upper furcation of the trigger seal 12", so as to hold the same in its cocked position. When the downwardly extending projection 2| I has swept across the recess 1-93, the spring loaded pin I01 will move out of engagement with the projectile -in' the magazine and will permit the projectile to move to the rear end of the magazine and into engage ment with the projection 2 on the arm 203. When the slide ispushed forwardly again, the slide cam'2i5 will move the downwardly extending projection 2 H of the arm 203-back across therecess and out of interference with'the delivery end of themagazine and the 'rearmost projectile in the magazine can drop into the recess I93. Again, the pin 19! has been pressed downwardly into the magazineto keep the next projectile therein. The forward movement of the slide. 2 l3 will cause the forward end of the pin 22! to move the pellet, in the breech end of the barreL forwardly beyond the passageway 2l",'as indicated in dot and dash lines in Fig. 14. The gun is then ready for firing. When the trigger is pulled,l the hammer is released and thrown forwardly by V the spring H" against the anvil '64" and the valve 28" is opened in the manner previously de-' scribed.

It will thus'be seen that the gun of this embodiment is automatically loaded and cooked at l the same time,so that it is not necessary to drop a projectile'into the barrel each time the gunflis' cocked,"as with theprevious embodiment. It will also be appreciated that with the construction of this embodiment, means are provided for indicating to the user of the gun when the air pressure in the storage chambers l5" and l B" is below the desired amount, and a novel type of compressor unit is illustrated. However, it will be appreciated that the valve 28" is opened, and operates,

in exactly the same manner as previously described, so that the gun of this embodiment is of the repeater type, for the same reasons and in the same manner set forth above.

What is claimed is:

1. A repeater type pneumatic gun including a' barrel through which a projectile may be shot, a storage chamber communicating with said bar-j reland adapted to contain a'volume of fluid at a relatively high pressure, valve means between said barrel and storage chamber for controlling the flow. of fluid from the chamber to said barrel, said valve means being normally held in a closed position by the fluid'pressure in said chamber, a hammer member supported in said gun for movement toward and away from said valve means in substantially the same direction as the direction of movement of said valve means and a sentee 1:9,: rel and-adapted to -contain avolumeof. fluid; at arelatively high pressure, valvemeansbetween saide-barrel and storage: chamber for controllingthefiow of fluid from the chamber to said-barrel, said valve means. being-tnormallyheld inla: closed position by the fluid pressure in said chamher, a hammer member supported: in. said gun for. movement toward and awayfrom saicb valve:

means in the-same direction -as' the @direction 1 i movement of said valve means and :adapted L to engage said valve means and i open th 1 same against thefluid-pressure in said chamber, means: for: actuating said-hammer. member and moving; the. same. towards said v valvelmeans; said means: including a spring: element engagingsaid hams merlmember. only; during aportion of;'its.- .move+- ment' toward! said valve means-,- whereby; said means: willbe-l disengagedifrom' said hammer: member before said valve means is engaged;

thereby: and opened; the movement of said ham-- mer: member 5 toward said valve" meanszandr the movement ofzsaid .hammerlandsaidavalveei'neansi afterssaidavalve ineanslahasbeen-engaged byisaid':

hammer member,,beingisubstantiallyunimpaired1 closedfpositionbyth'efiuidipressure.in saidchamber; ahammer' member supported-1 in" saidgunfor: nibvement toward and." aw'ayfrom said valve meansrandadapted to engage;- said: valvev means and'iopenl the same against-the: fluid; pressure in: said chamber; means-for: actuating saidhammer memberand moving the samertowardswsaid valve means said means including a spring-1 element engaging said hammer: member onlyduring: a

portion of its .movementtoward said valve-means, whereby said meanswillbe disengaged from said; hammer member before said valve 1 means is engaged therebyandopened, said hammer: member and valve means being movable in the direction ofactuation of said hammer by saidresilientameans until thev momentum thereon is overcome by the fluid-pressure insaid chamber-,at whiolitimerthe fluid: pressure? will-i move said valve, means and hammer member in the opposite, direction and close said valve-means. I

4. A pneumaticgunincludinga barrel throughl which a projectile is adapt'edto be shot, a storage chamber. adaptedto: contain avolume-of-l fluidand communicating with saidbarrel, said gun being: of. the type adapted to shoot a pluralityz of projectiles from-the barrel after said storage chamber is initially charged-Wampum:- under pressure, saidchamber having a fluid capacity such asto. be capable of supplying the rluid-necessary to propel a predeterminednumberof projectiles from said barrel allata substantially con stant velocity, v-alvemeansbetween saidbarreland-i storage chamber for controlling. the-flow of fluidfrom said chamber to said barrel, saidvalve meansbeing normally held in aclosedposition by the fluid: pressure. in said chamber, a ham-- mer member supportedin said gunlfor movement toward and away; from. said; valve means; and adaptedjto' engagesaidavalve-means. andiopen the same against the fiuid pressure in saidachamber; means for: actuating; said hammerymember and 201 movingthe. same toward saidvalve meanssaid means includi'nga spring element engagingsaid' hammer member only, during a. portion of, itsmovement toward said valve means wherebysaid' means will become disenga'gedtherefrom prior to. the. engagement ofj'said valve means by said hammerimember the weight of. said hammer member andthe force factor ofis'aid springelement being correlatedv such as to openthe valve means a plurality. of'times. such amounts and. for such periods of, time asltd permit a plurality ofiopro. jectiles to be. propelledi from. saidbarrel by,v fluid: pressure from .saidchamb'er, without-recharging thepressure in said chamber,.atsubstantially the samelmuzzle velocity, but-.innoicaseat amuzzle velocity-variance oflmoreithan-twenty, percent.

5 l A pneumatiegun includinga barrel through; whicha,pro;ectilerisiadaptedrto, be shot,. a; SlJOIrage-chamberadapted to. contain a volume of "fluid and communicatingwith saidlbarrel, saidgunv being of the typeadapted, toshoot a. pluralityof projectiles from the barrel; after said storage, chamber is. initially; charged with. fluid. under ressura-saidchamber having a fluid capacity:

- of fluid fromsaid chamber tosaidLbarrelrsaid valve means being normally held .in a closed-.-po,- sitionby the; fluid pressure in said, chamber, a: hammerimember supported in said gun formovementutoward-and away from said valve means and adapted to-engage said-valve-means and open thesame against thefluidfpressure in said chamber, resilient means movable from a compressed position toan uncompressed or.f-ree.. position to actuate-said hammer member and move the-same. toward said valve means, the Jength of travel-of said-v resilient means i from its compressed to uncompressed" position beingless than; the.- distance thewhammer: member moves gto-engagesaid valvemeanssorthat said resilient means becomesdisengaged-dram said hammer member prior. to the:- engagement'of. said valve-means by saidhammer member, the massof saidhammermember and. the'force exerted by said resilient means beingso related to the pressure in said storage chamberand the'zmass and size of said valve means; as to open said valve means a predetermined. distancefand fora predetermined length of time, in accordance with-the pressure insaid chamber,- so as to propel said plurality of projectiles from saidbarrelat a substantially uniform muzzle velocity, and topermit only the necessaryvolume of: fluid tofiovr to the'barrel each time said "valve means is opened such that the. necessary volume of fluid, at a sufi'iciently high pressure, will be present in the storage chamber to propel the last of said-predetermined number of projectiles from said barrel at substantially the same muzzle velocity as the prior projectiles propelled'from saidicharge of fluid.

6; A pneumatic gunincluding abarrel through which a projectile is adapted to be'shot, a. stor-- age chamber adapted to contain avolume of fluid and: communicating with said barrel, said gun beingofthetype adapted to shoot a plurality ofprojectiles from the barrel after said storage chamber is -initially charged with fluid; under pressure, said chamber having a fluid capacity, suchasto becapable of supplying theifiuid-necessary to propel; a predetermined numberrof pro:-- jectilesif-rom said barrel-all at a-substantially conw assume;

stant velocity, valve means between said'barrel the same against the fluid pressure in said chamber, resilient means movable from a compressed position to an uncompressed or free position to" actuate said hammer member and movethe same toward said valve means, the length of travel of said resilient means from its compressed to uncompressed position being less than the distance the hammer moves to engage said valve means so that said resilient means becomes dis.-.

engaged from said hammer member prior to the engagement of said valve means by said hammer member, the weight of said hammer member and the force exerted by said resilient means being correlated relative to each other such as to open saidvalve means for a predeterminedly greater length of time as the pressure in said storage chamber drops predetermined amounts, so as tomaintain the product of the length of time and the fluid pressure'substantially constant for a predetermined number of shots from said gun, whereby to maintain a substantially uniform muzzle velocity for the plurality of projectiles shot from said gun. l

'7. A repeater type pneumatic gun including a barrel through which a projectile is adapted to be shot, a storage chamber communicating with said barrel'and adapted to contain a volume of fluid at a relatively high pressure, valve means between said barrel and storage chamber for controlling the flow of fluid from the chamber to said barrel, said valve means including a valve seat and a valve'member normally urged into engagement with the valve seat by the fluid pressure in the storage chamber, a hammer member supported in said gun for movement toward and away from said valve means, means for moving said hammer member toward said valve means, an anvil supported in said gun for moving toward and away from said valve means and engageable by said hammer member for delivering an impact to said valve member sumcient to move the latter away from its seat against the fluid pressure 'insaid storage chamber. said hammer moving means including a resilient element movable from a compressedto an uncompressed position to actuate said ham; mer member and move the same toward said anvil, the length of travel of said resilient element from its compressed to uncompressed posi; tions, being less than the distance the hammer m'e'mber'moves to en a e said anvil so that said resilient element will become disengaged from said hammer member before the latter engages said anvil.

8. A repeater type pneumatic gun including a barrel through which a projectile is adapted to be shot, a storage chamber communicating with said barrel and adapted to contain a volume of fluid at a relatively high pressure, valve means between said barrel and storage chamber for controlling the flow of fluid from the chamber to said barrel, said valve means including a valve seat and a valve member normally urged into engagement with the valve seat by the fluid pressure in the storage chamber, a hammer member supported in said gun for movement toward and away from said valve means, means for moving said hammer member toward said valve means,

an anvil supported in said gun for movement toward and away from said valve means and engageable by said hammer member for delivering an impact to said valve member sufficient to move the latter away from its seat against th fluid pressure in said storage chamber, said hammer moving means including a resilient element movable from a compressed to an uncompressed position to actuate said hammer member and move the same toward said anvil, the length of travel of said resilient element from its compressed to uncompressed positions being less thanthe distance the hammer member moves to engage said anvil so that said hammer moving means-will become disengaged from-said hammer member before the latter engages said anvil,'and said hammer, anvil and valve member being substantially free to move in the direction of actuation of said hammer member until the momentum thereof is overcome by the fluid pressure in the storage chamber, at which time the fluid pressure I will return said valve member into engagement with said valve seat without having to overcome and communicating with said barrel, said gun being of the hand-ca'rriable repeater type adapted to shoot a plurality of projectiles from the barrel at a substantially uniform muzzle velocity after said storage chamber is initially charged with fluid under pressure, valve means between said barrel and storage chamber for controlling the flow of fluid from said chamber to said barrel, said valve means being normally held in a closed position by the fluid pressure in said chamber, a hammer'member slidably supported in said gun for movement toward and away from said valve means and adapted to engage said valve means and open the same against the fluid pressure I in said chamber, a spring element adapted to be cooked and released so as to'propel said hammer member toward said valve means as a free-floating mass, said spring element engaging said hammer member only during a portion of its movement toward said valve means, said hammer member being free to move substantially unimpaired toward and into engagement with said valve means, and said valve means being free to move substantially unimpaired except by the fluid pressure away from said valve seat so that the propelled movement of said hammer member mass will be uninter-' said valve means and reverse the direction of' movement of said hammer member.

10. A hand-carriable repeater type pneumatic gun including a barrel through which a projectile may be shot. a storage chamber communicating with said barrel and adapted to contain a volume of fluid at a relatively high pressure, means for compressing air in said storage chamber at a desired pressure, valve means between said barrel and storage chamber for controlling the flow of fluid from the chamber to said barrel, said valve means being normally held in a closed position by the fluid pressure in said chamber, a hammer member supported in said gun for movement toward and away from said valve means and adapted to engage said valve meanmandiopeni the :same..againstz thez-fiuid prese surein' said chambengresilient means supported in; said. gun. adjacent said. hammer. member: and; movableilfrom'i a: compressed to: an uncompressed positions to; actuate; said hammer member and. move: the same; toward said. valve. means,-, the

length: of. travel; of i said resilient means :from: its compressed: to, uncompressed positions being; less: than the distance said hammer: member? moves; to: engage-said valve means so.v that said resilient. means; wilt, become disengaged from; said: hammer-rmember before; said valve 'means'isen aged: by-saidrh'aimnen member and opened.

11; A: pneumatic; gun. including; a". barrel; through whichrazprojectilefis adaptedto beshot; a-storage chamber adapted tovcontain a: volume oifluid and communicating with saidLbarrel; saidgun:being;of the;type; adaptedvto shoot a, plurality of projectiles from the barrel; after said. chamber. is: initially charged with fluid under pressure; said chamber having aufluid capacity such as: to be capable of. supplying the fiuid; necessary to propel a: predetermined: number of projectiles fromsaid barrelgalha-t; a; substantially constant-velocity, valve means between; saidsbar rel and storage chamber for controlling. th flow of fluid from said: chamber to=said bar-reLsaid valve-means being'normally hel-d'ina closed po--- sition byth8'1fluid pressure in; said chamber; a hammer: member supportedinsaid-gun-formovement toward and awayfrom said valve-means and adapted to engage said valve means-andnpenthe-same against the fluid pressureinsaidcham ber, resilient means supported in: said gun and movable from a compressed toan uncompressed position to actuate said. hammermember and. move the same toward and into-engagement with saidvalve.- means; the length of travel; of saidresilient means from its compressed to uncom pressed positions being less than the distance said-hammer member moves-to engage said valve: means, so thatsaid jresilient meansbecomes dis engaged, from saidv hammer member before the latter engages said. valvemeans, saidhammer.-

member having. aweight; and said, resilient,

means exerting a force against said: hammer. member Which will maintainthe product of the length of time the valvemeans remains open and,

the fluid pressure flowing to said barrel'substa-nrtially constant for apredetermined number of shots fromsa id gun, whereby to maintain-a sub? stantially uniform muzzlevelocity. for the.- plusrality of projectiles-shot from the-gun..

12. A. pneumatic gun including: a; barrel; throughwhi-ch a proj ectileaisadapted. tojbe. shot, a storage-chamber adapted to contain:- avolume-- of fluid; andv communicating with, said; barreL. said, gun. being of thetype adapted toishoota plurality oft. projectiles from thebarrelr. after, saidstorage'chamber is initially charged: with fluid:

under: pressure; said; chamber:- having; a: fluid; ca,-

pacitysuch as: tobe: capable: of: supplying: the fluid: necessary:- to propel a; predetermined num-- ber of. proj ectiles; from; said barrel all: at. a. sub

stantially constant muzzle? velocity; valvezmeans between: said: barrel and storage chamber-i01 controlling the flow; of fluid. from said chamber to.- said" barreL; said: valve means being. normally: heldziir azclosedz position: byv 'the fluid pressure in said chamber; a, hammer member supported in said: gun: for; movement;- toward. and: away: from said; valve; means: and.' adapted: to. engage said valvezmeans; and open the same against the' fluid pressure; in": said chamber; spring-:: means 1 includ; ing. a spring portion for-actuating said hammer member; andmovingi the same: toward said valvev means, said; spring portion b.eing:movable=-.from:aa

compressed; to: an. uncompressed position. to. ac-

tuate' sai'd' hammer member and move: the same 5 toward and. into engagement: with said: valve means, thec-lengthof travel of said spring portion: from its compressed to uncompressed: post-- tions beingtless' th'anthe distancethe'hammer' member moves to engage said valve means; so. that said springtpurtionpbecomesdisengagedlfrom said hammer member? priorto' the engagement of: said valve means by said hammer member;

theweight ofsaid hammer'member and theforce of said: spring being: such as" to? open said; valve means; a predetermined amount and for aprerdetermined period of time eachztimesazi'di valve:

means is engaged by said hammermembenand such as; to open said valve means a great'erdistance andfora' longer periodiof time as-th'e fiuidt pressurein'said'storage chamber decreases, Whereby; asthe pressurexin' said storagechamber d'ecreases; said. valve means will be opened." for a:

greater periodtof'time -to permit'a larger volume of. fluid at a lower pressureitoibe'communicated'to thebarrel behind the projectile therein and shoot the projectile-fromthe barrel'at substantially thesame: muzzle velocity as the projectilev fired" be'- fore and-the projectile fired thereafter:

S. WELLS.

References Cited in' the file of thispatent UNITED STATES PATENTS 

